ACI 548.7-04 Test Method for Load Capacity of Polymer Concrete Underground Utility Structures.
10.2—Procedure 2: Vertical load evaluations for walls 10.2.1 Position the enclosure in the testing machine so that the test load is applied to the center of the longest wall. Place the loading pad so that 1/2 of it overhangs the edge of the box wall, leaving a 5 x 10 in. (125 x 254 mm) portion over the box and cover edge. Measure deflections perpendicular to the center of the box wall below point of load. Figure 4 illustrates an enclosure setup for edge load testing. Preload the specimen enclosure in the test apparatus to 20% of the design load before test loading to fully seat all components. Set deflection measuring gauges to zero after removing the preload. 10.2.2 Apply the test load in 10 incremental steps equal to 10% of the vertical design load. Record load and deflection at each load increment until the design load is reached. Hold the design load for 1 min and then reduce the load to zero in equal increments of 10% of the design load. Allow the enclosure assembly to rest at zero load for 1 min before resuming loading. 10.2.3 After reaching the design load, unload and reload the enclosure nine more times at a uniform speed. Each cycle includes loading to the design load within 1 min, holding the design load for 1 min, unloading within 1 min, and resting the specimen with no load for 1 min. 10.2.4 Permanent deflections shall be measured within 1 min of load removal after the last repetition. 10.2.5 Repeat the loading process given in Sections 10.2.1 through 10.2.4 on the other two specimens.
10.3—Procedure 3: Lateral load capacity evaluation for the walls 10.3.1 Position the enclosure in the testing machine so that a pneumatic bag installed between the enclosure specimen and a strong-back reaction frame loads the largest box wall from the outside (Fig. 5). The opposite sidewall shall be supported to achieve a uniform reaction, or it shall be supported on ribs or stiffeners so long as no local failure occurs. Ensure the pneumatic bag surface has a constant pressure and is in full contact with the test specimen before any load is applied. A deflection-measuring device shall be positioned to measure the deflection of the wall being tested relative to the two box end walls. If a compressible medium is used for a reaction base, its deflection shall be measured and subtracted from the total to yield to the deflection of the test wall.
10.4—Procedure 4: Failure loading 10.4.1 Use one of the three specimens, after completion of Procedures 2 and 3, and reload the cover to failure within 5 min using the test setup from Procedure 1. Record resulting deflections at 1000 lb ± 100 lb (4500 N ± 450 N) intervals with the deflection-measuring device used. Remove the deflection-measuring devices after reaching the design load and continue increasing the load until failure. Record the failure load and mode of failure. 10.4.2 Use one of the three specimens, after completion of Procedures 1 and 3, and reload the box to failure within 5 min using the test setup from Procedure 2. Record resulting deflections at 1000 lb ± 100 lb (4500 N ± 450 N) intervals with the deflection-measuring device used. Remove the deflection-measuring devices after reaching the design load and continue increasing the load until failure. Record the failure load and mode of failure. 10.4.3 Use one of the three specimens, after completing Procedures 1 and 2, and reload the box sidewall to failure within 5 min using the setup from Procedure 3. Record the resulting deflection at 50 lb/ft 2 ± 5 lb/ft 2 (0.0025 MPa ± 0.00025 MPa) intervals. Remove the deflection-measuring devices after reaching the design load and continue increasing the load until failure. Record the failure load and mode of failure.ACI 548.7 pdf download.